[Haskell-cafe] Annotated ASTs, and the tension between Bound, Free, and Cofree...

mikael.brockman at gmail.com mikael.brockman at gmail.com
Sun Aug 2 14:56:05 UTC 2015

Tom Ellis <tom-lists-haskell-cafe-2013 at jaguarpaw.co.uk> writes:

> Or if you want *every* subterm annotated then how about
>     newtype Expr f a = Expr { unExpr :: Free (ExprF (Compose f Expr)) a }

Merijn, if you get something like this working, I'd be interested to see
some of your code, since I too tripped over a similar problem when
looking for a nice way to represent annotated ASTs with bound. Having a
good solution seems like it would be widely useful.

-- Mikael Brockman

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